Alpha CD13R - Boiler Operation

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6.1 CENTRAL HEATING MODE
The operating sequence of the boiler is controlled by the selector switch on the control panel.
Setting the selector switch to position (2) the boiler will operate to provide central heating.
When the selector is set to central heating, it will respond to a demand for heat in the following sequence:-
a. The external pump will start, the fan will operate and the main burner will light.
b. The output of the burner is automatically controlled to suit the system demand.
c. When the temperature of the system water in the boiler reaches that set by the thermostat or the room thermostat is
satisfied, the main burner is turned off and the fan stops after 50 seconds. The pump will continue to run to remove any
residual heat from the boiler.
6.3 FROST THERMOSTAT
The boiler incorporates a built in frost thermostat which automatically turns on the boiler and pump if the water in the boiler falls
below 8°C, providing the electrical supply is on and the selector switch is set to position (1) or position (2). The boiler will
operate until the water temperature in the system reaches approximately 40°C.
6.4 PUMP
If the electrical supply is on and the boiler has not operated for 24 hours for heating or hot water, the external pump will operate
automatically for five minutes every 24 hours.
6.5 INDICATOR NEONS
When neons A (red), B (red), C (yellow), D (green) are illuminated, the following conditions apply:-
Neon
D Illuminated continuously - Electricity supply to the boiler is on.
C Illuminated continuously - Burner is alight.
A Flashing on and off - Temperature sensor fault.
B Flashing on and off - Overheat thermostat has operated. Rotate selector switch to the reset position (3) to reset.
B Illuminated continuously - Burner has failed to light. Rotate selector switch to the reset position (3) and the ignition
sequence will restart after a delay of about 30 seconds.
A and B Flashing on and off at the same time - Blocked flue or fan fault.
A Flashing and B Illuminated continuously - Pump fault or restricted flow.
A Illuminated continuously and B flashing - PCB or flame sensor fault.
A and B illuminated continuously - No flow or air present
A, B and C flashing on and off at the same time - Temperature sensor wiring or flow and return connections incorrect.
Note: Do not hold the selector switch in the reset position (3) for more than 2 to 3 seconds.
Alpha CD13R, 18R, 24R - Boiler Operation
6 BOILER OPERATION